Is the PCM device the same as the program-controlled switch?

The PCM device is a device that implements the remote extension of the subscriber line and is used for user service access, multiplexing, and transmission, and does not process user services.

The program-controlled switch is mainly used to realize the cross-interaction between internal telephones, just like the network switch, only the terminal object of the program-controlled switch is the telephone, and the terminal of the network switch is mostly the computer.

Expanded knowledge: Many customers can't distinguish the functions of optical transceiver and PCM devices.

Generally speaking: the PCM device transmission medium is a 2M coaxial cable, and the optical transceiver transmission medium is an optical cable.

PCM devices are only used for access and multiplexing of narrowband services and are not used for transmission.

The optical transceiver is used as a device for long-distance transmission.

The upper stage of the PCM equipment will be equipped with one transmission equipment for long-distance transmission. The main transmission medium of the domestic transmission network is the optical fiber, so a large part of the transmission equipment of the upper level of the PCM equipment is the optical transceiver.